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How to Use
- 1Enter text or a URL component in the input area.
- 2Click Encode to convert special characters to percent-encoded format.
- 3Click Decode to convert percent-encoded strings back to readable text.
- 4Use Swap or 'Output as Input' for iterative encode/decode operations.
- 5Copy the result with one click.
About URL Encoder/Decoder
The URL Encoder/Decoder converts between plain text and URL-encoded (percent-encoded) format using encodeURIComponent. Special characters like spaces, ampersands, and non-ASCII characters are replaced with %XX sequences for safe use in URLs.
Developers use this tool to construct query strings, debug URLs with encoded parameters, encode form data, sanitize user input for API requests, and decode percent-encoded values from server logs.
All encoding and decoding runs locally in your browser. No data is transmitted to any server — safe for encoding API keys, tokens, and sensitive parameters.
Frequently Asked Questions
What is URL encoding (percent-encoding)?
URL encoding replaces unsafe characters with a % sign followed by two hexadecimal digits. For example, spaces become %20 and & becomes %26.
Which JavaScript function is used?
encodeURIComponent() is used for encoding, which encodes everything except A–Z, a–z, 0–9, and the characters - _ . ~
Does the decoder handle + as a space?
Yes. The decoder normalizes + signs to spaces before decoding, supporting the application/x-www-form-urlencoded format used in HTML forms.
When should I URL-encode values?
Always encode user input before inserting it into URLs, query strings, form data, or API parameters. This prevents broken URLs and potential security issues.
Is my data sent to any server?
No. All encoding and decoding happens locally in your browser using native JavaScript functions. Your text never leaves your device.